Multiunit printing press



Junev 8, 1954 A. e. ROYER MULTIUNIT PRINTING PRESS Filed Dec. 9, 1949 IN VEN TOR.

Patented June 8, 1954 MULTIUNIT PRINTING PRESS Arthur G. Boyer, East Cleveland, Ohio, assignor to Harris-Seybold Company, Cleveland, Ohio, a corporation of Delaware Application December 9, 1949, Serial No. 132,000

13 Claims. 1

This invention relates to improvements in a multiunit printing press.

One of the objects of the invention is the provision of a press of this character which is compact and of simple and economical construction.

Another object is the provision of a compact multiunit press adapted for high quality printing.

Another object is the provision of a press of the character stated in which the units are relatively close together with a short length of web between successive units, and in which a single tensioning device may be employed for regulating the tension of the web as it travels through a plurality of units.

Another object is the provision of a press in which there are a series of pairs of opposed printing units, the units of each pair having a common impression cylinder, and the web traveling outward over one side of the impression cylinders and backward over the other side thereof.

Still another object is the provision of means for preheating a web in a multiunit printing press, especially a multiunit offset printing press, .and reheating it as it passes by each unit to the next, whereby the web as it travels through the machine carries enough heat to dissipate the moisture from the moistening apparatus and assist in the drying of the ink.

A further object is the provision of a multiunit printing press in which by a simple change in the threading of the machine the web may be printed in multiple colors on one side only or in which half of the units may be utilized as perfecting units.

Other objects and features of novelty will appear as I proceed with the description of that embodiment of the invention, which, for the purposes of the. present application, I have illustrated in the accompanying drawing, in which Fig. l is an elevational view, diagrammatic in character, of a multiunit offset printing press embodying the invention;

Fig. 2 is a fragmental plan view partly broken away to illustrate the web turning means at one end of the press, and

Fig. 3 is a diagrammatic elevational view of a pair of up and down units of modified form.

In the drawing I have illustrated a series of frames, indicated generally by the reference numerals H), H, l2 and I3. These frames are of course rigidly mounted and rigidly connected together. Platforms It for use by the press operator and his assistants are carried by the frames or otherwise as may be desired.

While in its broader aspects the invention is applicable to printing presses in general it has particular utility in connection with rotary offset presses, and is so illustrated.

Suitably journaled in each of the frames N there is an impression cylinder l5. pression cylinders are parallel to each other preferably with their axes in a single plane and are preferably equally spaced. They are geared to gether to rotate at the same speed. They are metal cylinders without covering of any sort.

Each of the cylinders H5 is a common impression cylinder for a pair of up and down offset printing units l6 and Il. Each unit [6 comprises a plate cylinder l8, with the usual inking mechanism I9 and dampening mechanism 20, and a blanket cylinder 2|. Cylinders 2| are of conventional construction, each embodying a softrubber blanket which is wound around the cylinder and secured at its ends in a narrow gap formed in the metal part of the cylinder. The gaps are indicated in the drawing at 22.

The units |l beneath the impression cylinders it are like the units It in all essential respects except that they are inverted. They have blanket cylinders 24 which are identical with blanket cy-linders 2| and are disposed directly beneath the corresponding cylinders l5, the axes of each group of three printing cylinders l5, 2| and 24 preferably lying in a vertical plane at right angles to the horizontal plane through the axes of cylinders i5.

Each of the frames I!) therefore carries two complete units I6 and H, and the frames are placed relatively as close together as possible, the distance between them being dependent upon the factor of providing sufficient Work space for the pressmen, and the factor of whether or not it is desired to have the different units operate and 21 which mounting may be of any conventional form. From the active roll 21 the web 28 passes upwardly around guide rollers 29 and 30, upward and forward over a roller 3|, forward over a roller 32 and downward to a nest of feeding rollers 33, from which it is fed forward-in a horizontal plane between the first pair of impression and blanket cylinders i5 and 2 I. Thence the web extends forward in the same plane through the three remaining printing units It between the respective impression and blanket cylinders 5 and 2|.

At the end of the 'press remote from the feed end the direction of travel of the web is reversed These im- 7 to form a lower run 28 which moves back under the impression cylinders l5 between those cylinders and the lower blanket cylinders 24. In effecting this change of direction the web may be turned over or not as the pressman may elect. When it is desired to cause all of the units to print on the same side of the web, the web turning means is by-passed and the web is directed over a tensioning roller 34 and downwardly around an idler roller 35 which is tangent with the lower run of the web, and thus into the lower run.

When on the other hand it is desired to turn over the web at this point in order to perfect the printing of the web on its return run, the web is caused to run around the tensioning roller 34, back under a turning bar 315, outwardly at right angles and over a pair of superposed rollers 31 and 31' spaced apart sufiiciently to cause the web to return beneath a second turning bar 38 and over that bar to dispose the return run 28 directly beneath impression cylinders [5. Roller 31' is adjustable horizontally for web length compensating purposes. Mechanism for accomplishing such adjustment being well known in the art, no illustration of the same is deemed necessary. Tensioning roller 34 is driven at a surface speed slightly in excess of the rate of travel of run 28 of the web. Traction wheels or rollers 39 may be adjusted to bear against the web passing over roller 34 with more or less pressure, thereby permitting more or less slip and controlling the degree of tension throughout the horizontal portion of run 28 of the web.

At the feed end of the press, return run 28.

of the web extends beneath another driven tensioning roller 40 which turns at a surface speed slightly greater than the rate of travel of run 28. By adjusting the traction exerted on the web by roller 40, that is by varying the pressure of traction rollers 4! against roller 46, the tension in the horizontal portion of the return run 28 is regulated. After the web passes the tensioning roller 49 it travels upwardly and around a set of three cooling rollers 42 and down through compensating rollers 43to a cutter and folder indicated generally at 44. The use of a cutter and folder at this point is optional however, as a cutter and stacker or other devices may be substituted if desired.

In the drawing four pairs of up and down printing units operating on the upper and lower runs of the web are illustrated. It will be appreciated that any other desired number of up and down pairs of units is contemplated. In the illustrated case the machine is set up for a four color perfecting job of printing. In the event that it is desired to print 5, 6, '7 or 8 colors on one side only of the web it is necessary merely to thread the web differently, no change in apparatus being required. In that event the outgoing run of the web is caused to travel over the top and outer side of tensioning roller 34 and then down over the outer and under sides of idler roller 35 and back through the lower printing units H between their blanket cylinders 24 and the various impression cylinders I5. Roller 35 is adjustable horizontally for length compensating purposes.

The arrangement of the web in a loop according to this invention and the use of pairs of printing units one above the other is economical of space and of machine framing, as Well as of the number of impression cylinders, and it is accomplished without impairing the quality of printing because every impression is a rubber to steel impression. By so disposing the gaps 22 in each up and down pair of blanket cylinders as to pass and contact the impression cylinder at the same instant, any variation in thrust imparted to the impression cylinder by one blanket cylinder is opposed by an equal variation in thrust imparted by the other blanket cylinder, so that vibration is minimized.

The fact that the distance between successive impressions in the upper and lower runs is small, renders it unnecessary to employ compensating means for increasing or decreasing the length of the web between units to maintain register. Web length compensating means is employed at the outer end of the web loop, that is after the web leaves the upper end printing unit and before it passes through the lower end unit. In the case in which the web is perfected in the lower run this compensation is accomplished by adjustment of roller 31'. In the case where the web is printed on one side only the compensation is accomplished by adjustment of the roller 35.

During the printing portion of each cycle the web is gripped at each printing unit between the impression and blanket cylinders of that unit. Minor variations in web tension may occur between successive units, but as the blanket cylinder gap of a unit passes the impression cylinder of that unit the grip exerted uponthe web by those cylinders is relieved momentarily and the tension on both sides of that unit is equalized. In the special case where all of the gaps along one run of the web are in phase the tension of the entire run is equalized at the instant the gaps pass the impression cylinders.

In the outgoing run of the loop the web runs through a heating chamber 46 in order to preheat the web. Also between the feeding rollers 33 and the first unit it and between successive units thereafter provision is made for reheating the web, as by means of infrared lamps 41. Thus the web is preheated before it enters the first unit [6 and its temperature is maintained during its travel between successive units thereafter. Hence the moisture and ink solvents absorbed by the webduring the printing operations are driven off largely by the heat in the web itself. At the outer end of the upper run 28 of the loop 'the web passes beneath a web drier 48. On the lower or return run 28 of the web it passes under further infrared lamps 49 disposed between successive printing units and between the last unit and the tensioning roller 48. Beyond this latter roller the return run of the web may also pass through the heating chamber 46 for a final heating prior to passing over the cooling rollers 42.

In the modification of Fig. 3 I have shown a pair of up and down printing units I6 and 11' each of which has its own impression cylinder, numbered 55 and 55 respectively. The upper run of the web does not contact cylinder 56 and the lower run does not contact cylinder 55. This arrangement has advantages in some instances, as for example when it is desired to avoid possible influence of one of a pair of units upon the other unit, or when it may be desirable to utilize impression cylinders of slightly different diameters in different units.

Although, in the illustrated form of the invention, the loop extends horizontally, which is the preferred arrangement, it will be understood that it could be disposed vertically or at an angle.

Having thus described my invention, I claim:

1. In a multicolor offset printing press, a plurality of parallel impression cylinders disposed with their axes in a single horizontal plurality of units disposed on one side of said plane, each of said units comprising a blanket cylinder in printing relation with one of said impression cylinders, a plurality of similar units on the opposite side of said plane each comprising a blanket cylinder in printing relation with one of said impression cylinders, web feeding and guiding means for directing a web from one end of the press outwardly between the impression cylinders and the blanket cylinders on one side of said plane and back between the impression cylinders and the blanket cylinders on the other side of said plane, means at the end of the press remote from the feeding end for reversing the direction of travel of the web, and means interposed betwe-n said reversing means and the outermost impression cylinder for turning over the web each group of one impression cylinder and two blanket cylinders being disposed with their axes substantially in a single vertical plane.

2. In a multicolor offset printing press, a plurality of parallel metallic impression cylinders disposed with their axes in a single plane, a plurality of units disposed on one side of said plane, each of said units comprising a blanket cylinder in printing relation with one or" said impression cylinders, a plurality of similar units on the op posite side of said plane each comprising a blanket cylinder in printing relation with one of said impression cylinders, web feeding and metering means for drawing a web into one end i of the press, directing it through the press between the impression cylinders and the blanket cylinders on one side of said plane to the opposite end of the press beyond the nearest impression cylinder, means for tensioning the web at the latter end of the press, means at the latter end of the press spaced from the nearest impression cylinder for reversing the direction of travel of the web and guiding it back'between the impression cylinders and the blanket cylinders on the other side of said plane to the first named end of the press, and means for tensioning the return run of the web at the said last named end of the press.

3. In a multicolor offset printing press, a plurality of parallel impression cylinders disposed with their axes in asingle plane, a plurality of printing units comprising said impression cylinders and a like number of blanket cylinders disposed directly opposite the impression cylinders in printing relation therewith, the blanket cylinders having gaps disposed all in the same phase, means for feeding a web into the press at one end thereof, and means for tensioning the web at the opposite end of the press, whereby any tendency toward uneven tension of the web between successive pairs of units is dispelled when the gaps pass the impression cylinders.

4. A multicolor offset printing press as defined in claim 1, comprising means at the end of the press remote from the feeding end for compensating for variations in web length, and similar means at the feeding end of the press acting on the return run of the web for compensating for variations in web length.

5. In a multicolor offset printing press, means for feeding and directing a web outwardly and back in a loop having parallel runs, a series of printing units operating on the web during its CRY iii

outward travel and a similar series for operating on the web during its return travel, a web turning means at the outer end ofthe loop disposed to discharge the web into the return run of the loop, a direction reversing roller disposed outwardly beyond said turning means and tangent with the return run of the loop, and a tensioning roller over which the web travels at the extremity of its outer run and from which the web may be directed selectively into said turning means or over said direction reversing roller.

6. In an ofiset printing press, a series of similar printing units each comprising a blanket cylinder and a smooth hard surfaced impression cylinder disposed in printing relation; said im-, pression cylinders having their axes in a common plane, and each of said blanket cylinders having a gap in its periphery means for feeding and directing a web through said units in a plane between the said cylinders of the respective units, and means beyond the remote ends of the series of units for maintaining tension on the web, whereby slippage of the Web as it is passed by the gaps tends to equalize web tension throughout the planar portion of the Web.

7. In a multicolor offset printing press, a plurality of parallel impression cylinders disposed with their axes in a single horizontal plane, a plurality of units disposed on one side of said plane, each of said units comprising a blanket cylinder in printing relation with one of said impression cylinders, a plurality of similar units on the opposite side of said plane each comprising a blanket cylinder in printing relation with one of said impression cylinders, web feeding and guiding means for directing a first run of the web from one end of the press outwardly between the impression cylinders and the blanket cylinders on one side of said plane and a second run of the web back between the impression cylinders and the blanket cylinders on the other side of said plane, means between said runs beyond the outermost impression cylinder for selectively turning over said web and reversing its direction of travel or for reversing the direction of travel merely, whereby the web may be printed on one side by the first plurality of units and on the 'other side by the second plurality of units or upon one side only by all of said units.

8. In a multicolor offset printing press, a plurality of parallel impression cylinders disposed with their axes in a single horizontal plane, a plurality of units disposed on one side of said plane, each of said units comprising a blanket cylinder in printing relation with one of said impression cylinders, a plurality of similar units on the opposite side of said plane each comprising a blanket cylinder in printing relation with one of said impression cylinders, web feeding and guiding means for directing an upper run of the Web from one end of the press outwardly parallel to said plane between the impression cylinders and the upper blanket cylinders and beyond the outermost impression cylinder in an extension of said upper run, a web heater disposed above and in operative relation with said web extension and turning bar means'beneath said extension adapted to turn over the web and direct it backwardly in a plane tangent to the said impression cylinders on their lower sides.

9. In a multicolor offset printing press, a plurality of parallel impression cylinders disposed with their axes in a single horizontal plane, a plurality of units disposed on one side of said plane, each of said units comprising a blanket 7 cylinder in printing relation "with' one of said impression cylinders, a plurality of similar units on the opposite side of said plane each comprising a blanket cylinder in printing relationwith one of said impression cylinders, web feeding and guiding means for directing an upper run of the Web from one end of the press outwardly parallel to said plane between the impression cylinders and the upper blanket cylinders, a transverse roller beyond said outermost impression cylinder over which an extension of the upper run of the web passes, turning bar means beneath said extension adapted to receive the web. from the lower side of said roller, turn it over and deliver it in a return run at a level tangent with the lower sides of said impression cylinders, and a second transverse roller below said first named roller for taking the web from the first named roller and directing it rearwardly in a plane tangent with the lower sides of said impression cylinders, whereby the web may be printed on one side by the first plurality of units and on the other side by the second plurality of units, or upon one side only by all of said units.

10. An ofiset printing press as defined in claim 9, characterized in that said lower transverse roller is adjustable bodily for varying the length of the web in the loop beyond the outermost impression cylinder.

11. In a web printing press, a plurality of pairs of offset printing units, each pair comprising a common hard surfaced impression cylinder, the blanket cylinders of the two units of each pair being disposed above and below the common impression cylinder in printing relation therewith, means for impelling and guiding the web outwardly and back in a loop one run of which contacts said impression cylinders on their upper sides and the other run of which contacts them on their lower-sides, means for preheating the web before it enters the first printing couple, whereby the absorbed heat acts upon the ink solvents immediately after their being deposited upon the paper, and means for reheating the web to compensate for heat loss as the web travels through the press.

12. In a multiunit offset printing press, a set of like blanket cylinders disposed with their 'axes in a single plane, a set of hard surfaced impression cylinders with their axes in a plane parallel to said first plane, each said impression cylinder being disposed in printing relation with one of said blanket cylinders to form a printing unit, said blanket cylinders having gaps in phase, and means at the opposite ends of the press for imposing tension on a web passing through the press, whereby the tension between units is equalized when the gaps pass the impression cylinders.

13. In a multiunit offset printing press, means for directing a web outwardly and back in a loop having two parallel runs, a set of like blanket cylinders disposed with their axes in a single plane, said cylinders being tangent to and on the outer side of the first run of the web loop, a second set of like blanket cylinders disposed with their axes in a plane parallel to the first named plane, the cylinders of the second set being on the outer side of and tangent to the second run of the web 100p, hard surfaced impression cylinders disposed between said runs in printing relation with the blanket cylinders of the two sets, the blanket cylinders of each set having gaps in phase, and means at the opposite ends of the press for tensioning both runs of the web.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 380,001 Tucker Mar. 27, 1893 508,918 Crowell Nov. 21, 1893 618,236 Ormsby Jan. 24, 1899 677,739 Firm July 2, 1901 724,457 Firm Apr. 7, 1903 752,896 Firm Feb. 23, 1904 849,454 Beeken Apr. 9, 1907 1,272,128 Scott July 9, 1918 1,996,639 Brunnings Apr. 2, 1935 2,003,798 Barber June 4, 1935 2,398,832 Jirousek Apr. 23, 1946 FOREIGN PATENTS Number Country Date 278,721 Germany Oct. 3, 1914 

